A chip on film (COF) method is a method in which a data line control circuit or a scan line control circuit is mounted on a flexible substrate formed with polyimide or the like in a film form and the flexible substrate is bonded to a terminal (hereinafter, referred to “mounting terminal”) provided on a terminal portion of an electrooptic substrate through an anisotropic conductive film by thermocompression. Further, when the data line control circuit or the scan line control circuit is mounted on the electrooptic substrate with the COF method, a connection portion between the mounting terminal on the electrooptic substrate and a terminal on the flexible substrate is generally sealed (molded) by a resin or the like. The connection portion between the mounting terminal on the electrooptic substrate and the terminal on the flexible substrate is sealed in order to protect the connection portion from humidity and dusts and reinforce the connection portion.
Further, a configuration in which the data line control circuit or the scan line control circuit is mounted with a TCP method can be employed (for example, see, JP-A-2000-242194). Alternatively, a configuration in which the data line control circuit or the scan line control circuit is arranged on a different substrate and is connected to the electrooptic substrate with a FPC can be employed.
For example, when the data line control circuit is mounted with the COF method, data lines are divided into a plurality of groups such as a right half group and a left half group, for example, and a data line control circuit is mounted on each group, in general. This mode is superior in terms of any of cost and accuracy in comparison with a mode in which driving of all the data lines is controlled by a single data line control circuit. In a mode in which the plurality of data line control circuits (or scan line control circuits) are mounted, mounting terminals for connecting flexible substrates on which the data line control circuits (or scan line control circuits) are mounted are arranged in parallel on a terminal portion along one side of the electrooptic substrate in many cases. Further, there is a large-sized electrooptic substrate for liquid crystal television receiver in which mounting terminals are arranged on a terminal portion in a matrix form.
However, there are problems in the mode in which the data lines (or scan lines) are divided into groups and the data line control circuit (or the scan line control circuit) is mounted on each group. For example, as the number of mounting terminals is increased, time and effort are required for a sealing process so that manufacturing cost is increased. In addition, there also arises a problem that a thickness of the entire electrooptic substrate is increased in the mode in which the mounting terminals for connecting the flexible substrates on which the data line control circuits (or scan line control circuits) are mounted are arranged in a matrix form of 2×2. The problem arises since the flexible substrates which are connected to the mounting terminals arranged in a draw-out direction of the flexible substrates are superimposed on one another, the flexible substrate at an upper side is lifted and a thickness is increased by the amount of elevation of a resin member which seals a connection portion between the flexible substrate at a lower side and the mounting terminal when the flexible substrates are laminated.